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Lary, C. W.

Publications and source records attributed to Lary, C. W..

3 recordsLinked to original sources

The genetic architecture of trabecular bone score and association with fracture: a genome-wide association and meta-analysis

BackgroundTrabecular bone score (TBS) is a texture-based measurement derived from DXA scans, which describes the distribution of mineral across the vertebral bodies. Identifying its genetic determinants is crucial for enhancing understanding of its biological basis and clarifying its relationship with fracture risk. MethodsWe conducted a large-scale genome-wide association study (GWAS) of TBS from 44,767 participants (95.08% European ancestry). Sex heterogeneity was assessed through sex-stratified GWAS. Post-GWAS analyses included functional annotation, gene-set enrichment analysis, and cis-expression quantitative trait locus (cis-eQTL) colocalization. Two-sample and multivariable Mendelian randomization (MR) were employed to investigate the causal effect of TBS on fractures. FindingsWe identified 33 independent variants associated with TBS, which explained 4.06% of TBS phenotypic variance. All the discovered signals map to previously identified BMD-associated loci. Additionally, we identified genetic variants in the RAB11FIP3 locus that exhibited a sex-heterogeneous effect, being associated with TBS exclusively in males. Functional annotation and colocalization identified functional genes related to TBS. The two-sample and multivariable MR analyses indicated that TBS potentially has an independent causal effect on fracture risk. InterpretationOur study unveiled 33 independent loci associated with TBS, all in BMD-associated loci. One locus was further identified as associated with TBS only in males. MR results suggested that genetically derived TBS may be causally associated with fracture risk at different sites, potentially beyond BMD. This study provides insights into the TBS genetic architecture and uncovers its potential clinical applications in fracture risk prediction. FundingAll funding information can be found in the Acknowledgements section. Research in contextO_ST_ABSEvidence before this studyC_ST_ABSOsteoporosis is a common disease prevalent in older adults, mainly diagnosed by low bone mineral density and disruption of bone architecture. While the genetic determinants of bone mass have been well studied, the genetic architecture of bone features beyond BMD remains largely unknown. Added value of this studyThis study presents a large genome-wide association meta-analysis of the trabecular bone score (TBS), a measurement of trabecular distribution of bone mineralization across vertebral bodies. Our study identified 33 independent variants associated with TBS and one association signal only in males. Functional annotation highlighted crucial genes related to TBS. The two-sample and multivariable Mendelian randomization (MR) analyses suggested that TBS may be causally linked with fracture risk, potentially independent of BMD. Implications of all the available evidenceOur study represents an expansion of the traditional bone density phenotype used in most previous skeletal genetic studies. Based on the findings that all of the significant loci for TBS have been previously identified in GWAS of BMD, we conclude that TBS-associated variants have pleiotropic effects affecting not only mineral density but also the distribution patterns of minerals in the cancellous bone. Continuing to perform genetic studies of new skeletal phenotypes beyond BMD could ultimately impact the management and prediction of osteoporosis patients.

genomics↗

Transcriptomic network analysis of brain and bone reveals shared molecular mechanisms underlyingAlzheimer's Disease and related dementias and Osteoporosis

Alzheimers disease and related dementias (ADRD) and Osteoporosis (OP) are two prevalent diseases of aging with numerous epidemiological associations, but the underlying molecular mechanisms contributing to this association are unknown. We used WGCNA (weighted gene co-expression network analysis) to develop transcriptomic networks in bone and brain tissue using two different studies to discover common molecular mechanisms. We used RNA-sequencing data from the dorsolateral prefrontal cortex tissue of autopsied brains in 629 participants from ROSMAP (Religious Orders Study and the Memory and Aging Project), including a subset of 298 meeting criteria for inclusion in five ADRD categories and the full set in a secondary analysis, and RNA array data from transiliac bone in 84 participants from the Oslo study of postmenopausal women. After developing each network, we analyzed associations between modules (groups of co-expressed genes) with multiple bone and neurological traits, examined overlap in modules between networks, and performed pathway enrichment analysis to discover conserved mechanisms. We discovered three modules in ROSMAP that showed significant associations with ADRD and bone related traits and four modules in Oslo that showed significant associations with multiple bone outcomes. We found significant module overlap between the two networks, most notably among those modules linked to canonical Wnt signaling and skeletal tissue homeostasis and development. These results were preserved with a network from the full ROSMAP cohort (n=629), which included a broader spectrum of participants. Our results require validation in experimental studies but show support for Wnt signaling as an important driver of pathology in OP and ADRD. We additionally show a strong link between Dementia with Lewy bodies and bone outcomes. These results have translational significance in the development of novel treatments and biomarkers for both ADRD and OP.

neuroscience↗

Social Isolation Causes Cortical and Trabecular Bone Loss in Adult Male, but not Female, C57BL/6J Mice

Social isolation is a potent form of psychosocial stress and is a growing public health concern, particularly among older adults. Even prior to the onset of the COVID-19 pandemic, which has significantly increased the prevalence of isolation and loneliness, researchers have been concerned about a rising "epidemic" of loneliness. Isolation is associated with an increased risk for many physical and mental health disorders and increased overall mortality risk. In addition to social isolation, older adults are also at greater risk for osteoporosis and related fractures. While researchers have investigated the negative effects of other forms of psychosocial stress on bone, including depression and PTSD, the effects of social isolation on bone have not been thoroughly investigated. The aim of this study was to test the hypothesis that social isolation would lead to bone loss in male and female C57BL/6J mice. 16-week-old mice were randomized into social isolation (1 mouse/cage) or grouped housing (4 mice/cage) for four weeks (N=16/group). Social isolation significantly decreased trabecular (BV/TV, BMD, Tb. N., Tb. Th.) and cortical bone (Ct.Th., Ct.Ar., Ct.Ar./Tt.Ar., pMOI, Ct.Por.) parameters in male, but not female mice. Isolated male mice had signs of reduced bone remodeling represented by reduced osteoblast numbers, osteoblast-related gene expression and osteoclast-related gene expression. However, isolated females had increased bone resorption-related gene expression, without any change in bone mass. Overall, our data suggest that social isolation has negative effects on bone in males, but not females, although females showed suggestive effects on bone resorption. These results provide critical insight into the effects of isolation on bone and have key clinical implications as we grapple with the long-term health impacts of the rise in social isolation related to the COVID-19 pandemic.

physiology↗